1. Field of the Invention
This invention relates to a screening member for separating solids from gaseous flowing media, especially steam, and more particularly refers to a new and improved cone-shaped screening member having a plurality of spaced annular screen elements disposed behind each other with the cross section of each element shaped as an obtuse triangle.
2. Description of the Prior Art
U.S. Pat. No. 3,958,966 discloses a screening member for separting solids from flowing gaseous media, especially steam, wherein the screening member is of conical shape and is built into a pipe line with its apex pointing against the flow direction. The screening member consists of screen elements having approximately the cross section of an obtuse triangle. The screen elements are arranged staggered one behind the other and with a diameter increasing from stage to stage, and two screen elements each define a flow channel which gradually changes into an outflow direction parallel to the oncoming flow direction.
In this screening member, the outer triangle sides of the individual elements are parallel to the direction of the oncoming steam flow. While this arrangement and design of the individual screen elements causes solids appreciably larger than the flow channel entrance to be held back reliably, there is danger that solid foreign bodies, which are only slightly larger than the narrowest cross section of the passage openings of the screen, would settle in the convergent part of the passage canal. This, among other things, may require cleaning the screen. In this event, the entire screen must be disassembled or must be made accessible from the outside, which is a time-consuming arduous procedure requiring generally shut down of the steam pipe.